scholarly journals Acetylation of Eugenol over 12-Molybdophosphoric Acid Anchored in Mesoporous Silicate Support Synthesized from Flint Kaolin

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2995 ◽  
Author(s):  
Alex de Nazaré de Oliveira ◽  
Erika Tallyta Leite Lima ◽  
Deborah Terra de Oliveira ◽  
Rômulo Simões Angélica ◽  
Eloisa Helena de Aguiar Andrade ◽  
...  
Keyword(s):  
Acetic Anhydride ◽  
Acid Catalyst ◽  
Kinetic Studies ◽  
Molar Ratio ◽  
Molybdophosphoric Acid ◽  
Mesoporous Silicate ◽  
First Order Kinetics ◽  
Eugenyl Acetate ◽  
Heterogeneous Acid Catalyst ◽  
Excellent Stability

A new prepared catalyst, 12-molybdophosphoric acid (HPMo) anchored to the mesoporous aluminosilicate AlSiM, synthesized from Amazon kaolin, was characterized and used as a heterogeneous acid catalyst for the production of eugenyl acetate by acetylation of eugenol with acetic anhydride. The effect of various reaction parameters, such as catalyst concentration, eugenol/acetic anhydride molar ratio, temperature and reaction time, was studied to optimize the conditions of maximum conversion of eugenol. The kinetics studies showed that in eugenol acetylation, the substrate concentration follows a first order kinetics. The results of activation energy was 19.96 kJ mol−1 for HPMo anchored to AlSiM. The reuse of the catalyst was also studied and there was no loss of catalytic activity after four cycles of use (from 99.9% in the first cycle to 90% in the fifth cycle was confirmed), and an excellent stability of the material was observed. Based on catalytic and kinetic studies, HPMo anchored to AlSiM is considered an excellent catalyst.

Enzymatic Synthesis of Eugenyl Acetate from Essential Oil of Clove Using Lipases in Liquid Formulation as Biocatalyst

2021 ◽  
Author(s):  
Leandro Santolin ◽  
Karina G. Fiametti ◽  
Viviane da Silva Lobo ◽  
João H. C. Wancura ◽  
José Vladimir Oliveira
Keyword(s):  
Essential Oil ◽  
Acetic Anhydride ◽  
Enzymatic Synthesis ◽  
Molar Ratio ◽  
Syzygium Aromaticum ◽  
Liquid Formulation ◽  
Promising Alternative ◽  
Eugenyl Acetate ◽  
Extensive Evaluation ◽  
Pharmaceutical Industries

Abstract In this research, eugenyl acetate, a compound with flavoring, antioxidant and antimicrobial properties, was obtained from essential oil of clove (Syzygium aromaticum) via liquid lipase-mediated acetylation. Clove essential oil was extracted by drag water vapor from dry flower buds and its physic-chemical characteristics were analyzed. For the enzymatic synthesis, an extensive evaluation of reaction parameters was accomplished through employment of distinct reaction temperatures, acetic anhydride to eugenol molar ratios, enzyme loads and three different lipases (a lyophilized enzyme produced by solid-state fermentation of sunflower seed with Penicillium sumatrense microorganism and others two commercial lipases – Lipozyme TL 100L and CALB L). Characterization by Infrared Spectroscopy and Nuclear Magnetic Resonance (1H NMR and 13C) was used to confirm the presence of eugenyl acetate in the samples. Through optimized conditions (55 °C, acetic anhydride to eugenol molar ratio of 1:1, 10 wt% of Lipozyme TL 100L), 91.80 % of conversion after 2 h was achieved to the eugenyl acetate production. With the results obtained, it was possible to conclude that the use of lipases in liquid formulation is a promising alternative for the synthesis of essential esters largely applied on food, cosmetic and pharmaceutical industries.

scholarly journals Green Production of Glycerol Ketals with a Clay-Based Heterogeneous Acid Catalyst

2019 ◽  
Vol 9 (21) ◽  
pp. 4488
Author(s):  
Amri ◽  
Gómez ◽  
Balea ◽  
Merayo ◽  
Srasra ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Acid Catalyst ◽  
Fourier Transform Infrared ◽  
Molar Ratio ◽  
Order Kinetic ◽  
Operational Variables ◽  
Heterogeneous Acid Catalyst ◽  
Acid Activated Clay

Glycerol remains a bottleneck for the biodiesel industry as well as an opportunity from the biorefinery perspective, having a notable reactivity as a platform chemical. In particular, glycerol ketals can be envisaged as oxygenates for fuel formulation. In this study, we have focused on the green synthesis of glycerol ketals by reacting glycerol with acyclic (acetone, butanone) and cyclic (cyclohexanone) ketones in the presence of an acid activated clay Tunisian AC in homogeneous systems under quasi-solventless conditions. These reactions were followed by on-line Fourier Transform Infrared Spectroscopy (FTIR) (namely, ReactIR 10). Firstly, the contacting time was selected studying the activity, stability and chemical characteristics of a set of catalysts. The 1-h activated clay AC was further characterized by X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electronic Microscopy with Energy Dispersive Spectroscopy (SEM/EDS). Finally, the effect of the main operational variables (catalyst concentration, reagents molar ratio, time and temperature) were checked and we reflected on adequate second-order kinetic models with partial first-order deactivation.

scholarly journals Mixed-Metal Oxide Catalyst for Liquid Phase Benzene Alkylation

2019 ◽  
pp. 217-234
Author(s):  
M. Alhassan ◽  
U. Z. Faruq ◽  
A. Galadima
Keyword(s):  
Reaction Time ◽  
Acid Catalyst ◽  
Product Yield ◽  
Molar Ratio ◽  
Solid Catalyst ◽  
Mixed Metal Oxide ◽  
Absorption Bands ◽  
Molar Ratios ◽  
Stirred Reactor ◽  
Heterogeneous Acid Catalyst

Development of cheaper, active and more ecofriendly heterogeneous acid catalyst is a challenge mitigating the petrochemical industries. CuO-MoO3/ZrO2 solid catalyst was prepared by impregnation using suitable precursor materials supported over zirconia. Upon calcination at 450°C for 2 h and activation (by soaking in 2M H2SO4 for 30 minutes), available techniques were employed for the characterization. The available oxides and minerals in the catalyst were revealed by the XRF and XRD profiles respectively. The catalyst crystallite size (131.6nm) was obtained using the Bragg’s equation from the latter. Thermal analysis showed three weight loss stages between (49.25-152.06°C), (152.06-559.47°C) and (559.47-752.0°C ) while presence of sulphate and zirconia oxides was revealed by the FTIR analysis due to appearance of absorption bands around 1225-980cm-1 and 700-600cm-1 respectively. The catalyst (1wt%) was tested for alkylation in a continuous stirred reactor at 80°C using variable (2:1, 4:1 and 10:1) benzene to 1-decene molar ratios. The effects of reaction time and molar ratios on the selectivity, conversion and yield were determined. The alkylation results showed that the catalyst is highly selective to 1-decylbenzene as low amount of side products was obtained. The product yield and conversion increased with reaction time and benzene /1-decene molar ratio while selectivity decreased with increase in benzene /1-decene molar ratio with time.

scholarly journals Acylation of isobutylbenzene with acetic anhydride on AlKIT-6 mesoporous acid catalyst

2021 ◽  
Vol 4 ◽  
pp. 128-135
Author(s):  
Prabhu Azhagapillai ◽  
Balachandran Sundaravel ◽  
Muthusamy P. Pachamuthu
Keyword(s):  
Acetic Anhydride ◽  
Acid Catalyst

An efficient heterogeneous acid catalyst derived from waste ginger straw for biodiesel production

2021 ◽  
Author(s):  
Hewei Yu ◽  
Yunlong Cao ◽  
Heyao Li ◽  
Gaiju Zhao ◽  
Xingyu Zhang ◽  
...  
Keyword(s):  
Acid Catalyst ◽  
Biodiesel Production ◽  
Heterogeneous Acid Catalyst

scholarly journals The Effect of Co-solvent on Esterification of Oleic Acid Using Amberlyst 15 as Solid Acid Catalyst in Biodiesel Production

2018 ◽  
Vol 156 ◽  
pp. 03002
Author(s):  
Iwan Ridwan ◽  
Mukhtar Ghazali ◽  
Adi Kusmayadi ◽  
Resza Diwansyah Putra ◽  
Nina Marlina ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Amberlyst 15 ◽  
Acid Esterification

The oleic acid solubility in methanol is low due to two phase separation, and this causes a slow reaction time in biodiesel production. Tetrahydrofuran as co-solvent can decrease the interfacial surface tension between methanol and oleic acid. The objective of this study was to investigate the effect of co-solvent, methanol to oleic acid molar ratio, catalyst amount, and temperature of the reaction to the free fatty acid conversion. Oleic acid esterification was conducted by mixing oleic acid, methanol, tetrahydrofuran and Amberlyst 15 as a solid acid catalyst in a batch reactor. The Amberlyst 15 used had an exchange capacity of 2.57 meq/g. Significant free fatty acid conversion increments occur on biodiesel production using co-solvent compared without co-solvent. The highest free fatty acid conversion was obtained over methanol to the oleic acid molar ratio of 25:1, catalyst use of 10%, the co-solvent concentration of 8%, and a reaction temperature of 60°C. The highest FFA conversion was found at 28.6 %, and the steady state was reached after 60 minutes. In addition, the use of Amberlyst 15 oleic acid esterification shows an excellent performance as a solid acid catalyst. Catalytic activity was maintained after 4 times repeated use and reduced slightly in the fifth use.

scholarly journals Immobilizing Ni (II)-Exchanged Heteropolyacids on Silica as Catalysts for Acid-Catalyzed Esterification Reactions

2019 ◽  
Vol 65 (1) ◽  
pp. 21-27
Author(s):  
Qiuyun Zhang ◽  
Dandan Lei ◽  
Qianqian Luo ◽  
Taoli Deng ◽  
Jingsong Cheng ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Oleic Acid ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Kinetic Studies ◽  
Esterification Reaction ◽  
High Oleic ◽  
Ft Ir ◽  
Structural Surface ◽  
Esterification Reactions

Biodiesel was synthesized from oleic acid using Ni (II)-exchanged heteropolyacids immobilized on silica (Ni0.5H3SiW / SiO2 ) as a solid acid catalyst. Based on detailed analyses of FT-IR, XRD, TG and SEM, the structural, surface and thermal stability of Ni0.5H3SiW / SiO2 were investigated. Obtained results demonstrated that the Keggin structure was well in the immobilization process and possess a high thermal stability. Various esterification reaction conditions and reusability of catalyst were studied. High oleic acid conversion of 81.4 % was observed at a 1:22 mole ratio (oleic acid: methanol), 3 wt. % catalyst at 70 °C for 4 h. The Ni0.5H3SiW / SiO2 catalyst was reused for several times and presented relatively stable. More interestingly, the kinetic studies revealed the esterification process was compatible with the first order model, and a lower activation energy was obtained in this catalytic system.

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